Updates xml error unmarshalling to look at all request id keys when populating error information

Author: cenedhryn

.changes/next-release/bugfix-AWSSDKforJavav2-a6e2ed8.json

@@ -0,0 +1,6 @@
+{
+    "category": "AWS SDK for Java v2", 
+    "contributor": "", 
+    "type": "bugfix", 
+    "description": "Fixes a bug in XML error unmarshalling where error responses with empty body won't populate the requestId field. Affects Amazon S3 API calls such as Head object"
+}

core/protocols/aws-query-protocol/src/main/java/software/amazon/awssdk/protocols/query/internal/unmarshall/AwsXmlErrorUnmarshaller.java

@@ -19,6 +19,7 @@
 
 import java.time.Duration;
 import java.util.List;
+import java.util.Map;
 import java.util.Optional;
 import java.util.function.Supplier;
 import software.amazon.awssdk.annotations.SdkInternalApi;
@@ -27,6 +28,7 @@
 import software.amazon.awssdk.awscore.exception.AwsServiceException;
 import software.amazon.awssdk.core.SdkBytes;
 import software.amazon.awssdk.core.SdkPojo;
+import software.amazon.awssdk.core.http.HttpResponseHandler;
 import software.amazon.awssdk.core.interceptor.ExecutionAttributes;
 import software.amazon.awssdk.core.interceptor.SdkExecutionAttribute;
 import software.amazon.awssdk.http.SdkHttpFullResponse;
@@ -175,7 +177,16 @@ private String getRequestId(SdkHttpFullResponse response, XmlElement document) {
                                        .orElse(document.getElementByName("RequestID"));
         return requestId != null ?
                requestId.textContent() :
-               response.firstMatchingHeader(X_AMZN_REQUEST_ID_HEADER).orElse(null);
+               matchRequestIdHeaders(response);
+    }
+
+    private String matchRequestIdHeaders(SdkHttpFullResponse response) {
+        return HttpResponseHandler.X_AMZN_REQUEST_ID_HEADERS.stream()
+                                                            .map(h -> response.firstMatchingHeader(h))
+                                                            .filter(Optional::isPresent)
+                                                            .map(Optional::get)
+                                                            .findFirst()
+                                                            .orElse(null);
     }
 
     /**